textproduct: Albany

WHAT HAS CHANGED

Minor adjustments to POPs through Monday to better align with high resolution guidance and increased winds for tonight in western New England as the low-level jet increases. Then, lowered temperatures for tomorrow given high confidence for easterly winds maintaining cold air wedged near the sfc.

KEY MESSAGES

1) Widespread 0.5 to 1.5 inches of rain this afternoon through tomorrow across eastern NY and western New England. No flooding concerns.

2) Temperatures trend warmer Tuesday and Wednesday with an increase for showers for the middle to end of the week.

DISCUSSION

KEY MESSAGE 1...

Latest radar reflectivity shows a uniform area of stratiform focused mainly south of I-90 with a sharp northern cut-off around the Capital District. This is attributed to a strong area of confluence positioned between high pressure settled over northern New England an area of low pressure near the OH/MI border tracking northeastward. While the main sfc warm front remains well to our south in the Carolinas, the leading edge of a region of mid-level moisture and FGEN has advanced through the mid-Hudson Valley, eastern Catskills, central and southern Taconics, and NW CT with the NYS mesonet showing a few hundredths up to around two tenths in parts of the eastern Catskills has accumulated in the last 6 hours as of 1 PM. The incoming rain shield has since "hit the brakes" as it nears the Capital Region given upper level confluence with area from Albany north and eastward dry, cloudy, and seasonably cool in the low 60s. However, conditions will gradually deteriorate for the Capital District and the I-90 corridor towards 18 - 21 UTC as the mid- level ridging and stronger mid-level FGEN/moisture slowly advances northward. Still, the Upper Hudson Valley, northern Herkimer/Hamilton County and the CT River Valley in southern VT will likely remain dry through sunset as they remain north of the main forcing.

The wettest time period for the entire region looks to be from 06 UTC tonight through 18 UTC tomorrow as the leading edge of the mid-level FGEN finally pushes northeastward with a strong southeasterly 40-45kt jet in the 925 - 850hPa layer directing moisture off the Atlantic into the region. PWATs surge to 1 - 1.3" with warm cloud depths nearing 10kft. Efficient warm rain processes should support periods of steady, moderate rain at times, especially south of I-90, through early afternoon tomorrow. Western New England turns breezy towards and after 06 UTC tonight thanks to the incoming jet and slightly deeper boundary layer with gusts in the southern Greens, Taconics, Berkshires, and Litchfield Hills reaching 25 to 30kts. After 18 UTC tomorrow, the strongest warm air and moisture advection escapes to our east as a secondary weak coastal low tracks up the East Coast. Rain becomes lighter and scattered in the afternoon from west to east. However, it will still be a raw, chilly late May day as we remain north of the sfc warm front and easterly winds maintain a wedge of cool air near the sfc. In fact, probabilistic guidance shows greater than a 75% chance for all of eastern NY and western New England to struggle to rise out of the 50s. Lingering scattered light showers continue Sunday night as weak warm air advection continues between the exiting coastal low and a shortwave approaching from the Great Lakes. Probabilistic guidance shows greater than a 75% chance for 0.75 inches of rain throughout eastern NY and western New England through 12 UTC Monday with even a medium to high chance for amounts to exceed 1.25" in the eastern Catskills, mid- Hudson Valley, and NW CT. Luckily, no flooding issues expected given recent dry antecedent conditions.

The sfc warm front that has been to our south most of the weekend finally lifts to our north Monday morning. Meanwhile, a rather vigorous shortwave trough centered near the Hudson Bay tracks eastward on Monday as it becomes negatively tilted. The Northeast actually becomes positioned in the right entrance region of a jet streak with falling heights resulting in a weak sfc low in western NY that drags a sfc cold front eastward late Mon A.M into the early P.M. While we briefly enter the warm sector ahead of the front, the rather early arrival time of the front will likely limit the amount of instability that can develop. Should the front be delayed until later in the afternoon, chance for thunderstorms will likely increase but the current forecast shows chances for thunder remaining south and west of our area. In the wake of the front Monday afternoon, forecast soundings show deep boundary layer mixing ensuing leading to a warm and pleasant Memorial Day afternoon rising well into the 70s across the area.

KEY MESSAGE 2..Temperatures trend warmer Tuesday into Wednesday as sfc high pressure and zonal flow aloft takes shape. Probabilistic guidance even shows medium to high confidence in high temperatures in valley areas exceeding 80 degrees both days. While the forecast stays dry for Tuesday, there is strong agreement in the medium range guidance for an omega block to develop across the Central Plains with a shortwave in southern Canada diving southward during the middle of the week. As stated in the previous discussion, there are some timing differences but the consensus is for the shortwave and associated sfc cold front to track south and eastward through the Northeast on Wednesday. Depending on the timing, this can result in our next chance for showers and even thunderstorms. Temperatures then trend cooler for the second half of next week as northwest flow persists and additional shortwaves tracking within the amplified NW flow result in additional chances for showers.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

Through 18z/Sunday...Flying conditions are currently VFR even with light rain showers already at KPOU. KENX radar shows the precipitation shield just beginning to reach KALB and KPSF at the start of the TAF period. Cigs will continue to lower as showers move northeast this afternoon. KPOU will lower to MVFR first this afternoon around 20z as ongoing showers continue followed next by KPSF with possible patchy areas of showers beginning around 23z. KALB vis will lower to MVFR this evening around 00z as showers become more steady. KGFL will likely remain VFR and dry the longest until rainfall lowers vis to MVFR tonight after 03z. Hi-res guidance suggest the initial batch of rain may slightly let up towards the middle of the night but another round of steadier and slightly heavier rainfall is expected for all sites by the late night hours and through daybreak tomorrow. IFR flying conditions are likely at all the terminals after 12z tomorrow morning through the remainder of the TAF period.

Current winds from the south/southeast at KALB and KPSF around 10-15 kt will remain through the afternoon before decreasing 5-10 kt overnight. Winds at KGFL and KPOU are generally 5 kt or less this afternoon but will begin to increase overnight tonight to 5-10 kt. Winds into tomorrow afternoon shift out of the northeast and pick up again 10-15 kt with occasional gusts up to 25 kt, especially at KPSF.

Outlook...

Sunday Night: Moderate Operational Impact. Chance of SHRA. Memorial Day: Moderate Operational Impact. Chance of SHRA. Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: Low Operational Impact. Slight Chance of SHRA...TSRA. Wednesday Night: Low Operational Impact. Slight Chance of SHRA. Thursday: Low Operational Impact. Slight Chance of SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.